As soon as may be after such petition shall be referred to said commissioners, or within such time as the court or chancellor may direct, the commissioners shall meet and go upon said lands and examine the same, and the lands over which the work is proposed to be constructed, and determine: first, the starting point, route, and termini of the proposed work, the location and size of the main ditch to be constructed in said drainage district, which in their opinion will successfully drain the said lands, and whether the drainage of the lands in such proposed drainage district is possible or not, provided that any ditch already constructed in such proposed drainage district may be used as a “main”, or part of a main ditch, if found expedient and sufficient for the purposes of the district; second, the probable cost of same, including expenses and court costs; third, what land will be injured or damaged by the proposed work and the probable aggregate amount of damages such lands will sustain by reason of the laying out and construction of such ditch or ditches; fourth, what lands will be benefited by the construction of the proposed work, and whether the aggregate amount of benefits will equal or exceed the cost of the construction of such work. In the examination of such district and determination of the questions for said commissioners to determine, the said commissioners are authorized and empowered to employ an engineer to go with them upon the lands of said district and examine the same, make a map and profile thereof, and an estimate of the size and depth of the ditch or ditches required for main outlets for the drains of said lands, and the probable cost, and a profile thereof.